Circular hole cutter



E. D. WORTHAM CIRCULAR HOLE CUTTER June 11, 1957 2 Sheets-Sheet 1 FiledDec 29, 1953 A I INVENTOR. h/a/Zfifl Z77 ATTD R N EYE June 11, 1957 E.D. WORTHAM 2,795,277

CIRCULAR HOLE CUTTER.

Filedbec. 29, 1955 I 2 SheetsSheet 2 FIG. 7

) INVENTOR EDGAR D. WOR-THAM ATTORNEYS Uite This invention relates tomanually actuated cutting tools particularly adapted for cuttingopenings for fire prevention in gasoline tanks, oil tanks, barges, shipsand the like, and in particular a tool adapted to be temporarilyinstalled from the outside of a tank or other vessel and having an armwith scribing and cutting elements thereon mounted on a bushing threadedon a center stud and in which the stud is provided with a head having aslot for a key or link extended therethrough whereby with the headinserted through and secured in an opening in a plate by the key and alock nut, rotation of the arm with the cutting elements held in cuttingrelation with the plate by a spring on the bushing causes the cuttingelements to cut a disc from the plate.

The purpose of this invention is to provide a manually actuated cuttingtool that may readily be set up for operation from the outside of a tankor the like whereby openings may readily be cut in vertical walls oftanks and the like without cleaning or gas freeing and also wherein suchopenings may be cut in the least possible time.

With conventional methods of forming openings for fire prevention andthe like in gas and oil tanks, barges, ships, and the like it isnecessary to clean and gas free a tank before starting the cuttingoperation, and this requires from fifteen to twenty days. Also incutting such openings with conventional methods there is a tremendoushazard, owing to the gas and oil fumes.

With this thought in mind this invention contemplates a cutting toolmounted on a threaded stud with the head of the stud adapted to beinserted through a bolt hole in the wall of a tank or the like andsecured in said hole from the outside of the tank, and wherein theCutting tool is carried by an arm having hand gripping handles on theends rotatably mounted on the stud and having scribing and cuttingelements adjustably mounted thereon and whereby with the head of thestud clamped in the opening upon rotation of the arm a spring forces thecutting elements into operative relation with either a flat or curvedplate.

The object of this invention, is therefore, to provide a tool forcutting a circular opening in a plate, such as the wall of a tank inwhich the device may readily be mounted in an opening, such as a bolthole in the wall of the tank.

Another object of the invention is to provide a manually, actuatedcutting tool for forming circular openings in walls of tanks in whichtension applied to cutting elements of the tool is readily adjustable.

Another important object of the invention is to provide a circle cuttingtool having scribing and cutting elements carried by a stud temporarilymounted in an opening of a plate wherein the scribing cutter pushes andcuts and a cutting wheel pulls and cuts whereby with both the scribingarid cutting elements and cutting wheel working jointly a completelysmooth and even cut is obtained in a fiat wall of a tank.

' atent A further object of the invention is to provide a hand actuatedtool for cutting circular openings in circular walls of tanks and thelike in which the tool is of a simple and economical construction.

With these and other objects and advantages in view the inventionembodies an elongated threaded sud having a head with a transverselydisposed slot therein, and a key slidably mounted and frictionallyretained in said slot and adapted to be supported in an inclinedposition in the slot of the stud as the stud is inserted in an openingin a wall of a tank, and said key being adapted to be turned to avertically disposed position, transversely of the stud, to prevent thestud being withdrawn through the opening whereby the stud is adapted tobe used for mounting cutters for cutting an opening in a verticalwall'of a tank.

Other features and advantages of the invention will appear from thefollowing description taken in connection with the drawing, wherein:

Figure 1 is a side elevational view of the improved circle cutting toolshowing the device mounted on a plate, such as the vertical wall of atank, the plate being shown in broken lines.

Figure 2 is a plan view of the tool, one of the arms of the tool beingbroken away.

Figure 3 is a vertical section through the tool taken on line 3-4) ofFigure 1 showing the locking nut, bushing and elements mounted thereonand showing the stud in elevation, the lower end of the stud beingbroken away and a plate such as the vertical wall of a tank and uponwhich the device is positioned being shown in broken lines.-

Figure 4 is a detail showing the lower end of the stud, the upper partthereof being broken away and the stud being shown in a plate which isillustrated with broken lines.

Figure 5 is a section through the end of the stud taken on line 55 ofFigure 4 illustrating the position of the locking key in the slot in thehead of the stud and showing the parts in a vertical wall of a tankwhich is also illustrated in broken lines.

Figure 6 is a view looking upwardly toward the under surface of thelocking washer positioned around the lower part of the stud.

Figure 7 is a view showing a section through a por-' tion of a tank andalso through an end of a stud illustrating the inclined position of akey being inserted through an opening in a wall of a tank by the stud,the parts being shown on an enlarged scale.

Figure 8 is a view similar to that shown in Figure 7, showing the keyretained in position by the curvature of one side at the lower end, andwith the upper end held by the end of the stud.

Figure 9 is aview also similar to the views shown in Figures 7 and 8,showing the key drawn backward against the inner surface of the tankwall by the stud, and also showing the key in the position shown inFigure 8, in broken lines therein.

Although the cutter is shown as being used in a horizontal wall of atank for the purpose of illustration, it will be understood that thedevice is used to cut circular openings in vertical walls of cylindricaltanks and particularlywith the opening spaced from the upper edge of thewall.

Referring now to the drawing wherein like reference characters denotecorresponding parts the improved circular opening cutter of thisinvention includes an elon-i gated threaded stud 10 having a head 11witha key 12 extended through a slot 13 therein, a locking washerpositioned on the stud, a lock nut 15 threaded on the stud andpositioned to clamp the washer 14 against one sur-f face of a plate orwall of a tank, as indicated by'th'e nu meral 16 with the key 12 inengagement with the opposite side of the wall, a bushing 17 having aflange 18 on one end also threaded on the stud and having a section 19which is provided with flat sides, adjacent the outer end, an arm 20having a hub 21 which extends over the bushing 17 and provides means forrotatably mounting the arm on the bushing, a spring 22 positioned aroundthe bushing and extended between the hub 21 and a hub 23 of a handactuated crank 24, a nut 25 threaded on a section 26 at the outer end ofthe bushing, a socket 27 for adjustably mounting a cutting wheel 28 onone side of the arm 20 and a socket 29 for adjustably mounting ascribing point 30 on the opposite end of the arm.

As illustrated in Figure 3, the head 11 of the elongated threaded stud10 is adapted to be inserted through an opening, such as the opening 31in a tank wall, such as the plate 16 and with the key 12 retained in aninclined position in the slot 13, as shown in Figures 7 and 8, andturned through an angle ,of 90 after being inserted through the openingthe end portions of the key are adapted to be drawn against the cornersof the plate with fingers 32 and 33 on one side and 34 and 35 on theother side of the locking washer 14 straddling the key 12, asillustrated in Figure 4. By this means the key is retained in positionand the locking nut 15, which is threaded on the stud 10 is turned untilthe key and washer 14 are positively clamped against opposite surfacesof the plate or wall 16.

The sockets 27 and 29 are provided with openings through which the endsof the arm 20 extend and, as illustrated in Figure l, the socket27 isprovided with a. set screw 36 by which the socket may be secured inadjusted positions on the arm. The socket 27 is also provided with asleeve 37 having a set screw 38 therein and a stem 39 of a yoke 40 issecured in the sleeve 37 with the set screw whereby a cutting wheel 28,rotatably mounted in the yoke 40 with a pin 41 may be positionedtoengage a tank wall, such as the plate 16, upon which the cutting tool ismounted.

The socket 29 is also provided with a set screw, such as the set screw42 and a sleeve 43 extended from the hub 29 is provided with a bore 44in which a point, such as the scribing point 30 may be held by a setscrew 45.

By this means a scribing point may be set a predetermined distance fromthe center of the stud so that a circle may be described on the surfaceof a plate or wall of a tank or the like and with the cutting wheel 28set to the same dimension the plate may be cut on the line described bythe point 30.

The arm 20 is provided with graduations 46 on one side and 47 on theother and handles 48 and 49 are pro vided on the extended ends.

With the tool provided in this manner an opening, such as the opening 31may be drilled through a plate or upper part of a vertical wall of atank, and the head of the stud with the key 12 in the slot 13 thereofmay be inserted through the opening and the parts assembled by firstplacing the washer 14 on the plate with the fingers straddling theadjacent side of the key 12 and this washer is secured in position withthe lock nut 15 which also secures the stud in the wall. I

The bushing 17 is then threaded on the stud with the arm 20. spring 22and hand crank 24 secured thereon by the lock nut 25 and with thescribing point and cutting wheel set to desired positions the arm isrotated whereby the cutting wheel cuts the plate. The spring 22 providescushioning means relieving the cutting tool when the tool is fed toofast.

This cutter, which is completely installed and assembled from theoutside of a tank, is designed whereby it will cut uniformly on a fiatsurface and also on a curved surface such as the wall of a tank, and isparticularly adapted for cutting openings for flanges from two inches tothirty inches in diameter without gas freeing the tank and also withoutthe usual loss of time resulting from tying up the tank, barge, ship orthe like.

The key 12 is machined to a close fit in the slot 13 and as the studwith the key in an inclined position therein passes through an openingin a tank wall, as shown in Figures 7 and 8, the lower end of the keyrides upon the surface of the Wall at the lower edge of the openingtherein, and the upper end is held by the end surface of the stud at theouter end of the slot. After passing through the opening in the wall thekey is retained in position by the arcuate surface at the lower endresting upon the corner at the edge of the tank wall, and as soon as thekey reaches this position the stud is drawn outwardly whereby the key issnapped to the positon shown in full lines in Figure 8.

It will be understood that modifications, within the scope of theappended claims, may be made in the design and arrangement of the partswithout departing from the spirit of the invention.

What is claimed is:

1. In a circle cutting tool, the combination which comprises anelongated threaded stud having a head with a slot therethrough, a keypositioned in the slot in the head of the stud, a locking washer havingpairs of spaced fingers extended therefrom with the fingers positionedto straddle said key for retaining the key in the slot, a lock nutthreaded on the stud and positioned to engage the washer, a bushingthreaded on the stud, an arm having handles on extended ends thereofrotatably mounted on said bushing, a hand crank mounted on the bushingand adapted to rotate the bushing, a lock nut for securing the handcrank on the bushing, a scribing tool adjustably mounted on one end ofthe arm and a cutting wheel adjustably mounted on the opposite end ofthe arm.

2. In a eircule cutting tool, the combination which comprises anelongated threaded stud having a head with a slot therethrough, an openelliptical shaped key positioned in the slot in the head of the stud, alocking washer having pairs of spaced fingers extended therefrom withthe fingers positioned to straddle said key for retaining the key in theslot, a lock nut threaded on the stud and positioned to engage thewasher, a bushing threaded on the stud, an arm having handles onextended ends thereof rotatably mounted on said bushing, a hand crankmounted on the bushing and adapted to rotate the bushing, a spring onthe bushing positioned to urge the arm away from the hand crank, a locknut for securing the hand crank on the bushing, a scribing tooladjustably mounted on one end of the arm and a cutting wheel adjustablymounted on the opposite end of the arm.

3. A circle cutting tool comprising an elongated threaded stud, saidstud having a transversely disposed slot in one end, a key the length ofwhich is greater than the width frictionally retained in the slot of thestud, a washer having spaced pairs of fingers extended from one sidemounted on the stud and positioned with the fingers adapted to straddleand frictionally engage said key, said fingers being positioned toretain the key in an inclined position in the slot of the stud as thestud is passed through an opening in a plate and to permit the key to bemoved to a transversely disposed position to prevent withdrawal of thestud from an opening in a plate, an arm rotatably mounted on said stud,and a cutter carried by the arm and positioned to cut the plate uponrotation of said arm.

4. A circle cutting tool comprising an elongated threaded stud, saidstud having a transversely disposed slot in one end, a key the length ofwhich is greater than the width frictionally retained in the slot of thestud, a washer having spaced pairs of fingers extended from one sidemounted on the stud and positioned with the fingers adapted to straddleand frictionally engage said key, said fingers being positioned toretain the key in an inclined position in the slot of the stud as thestud is passed through an opening in a wall of a tank and to permit thekey to be moved to a transversely disposed position to preventWithdrawal of the stud from an opening in a wall, an arm rotatablymounted on said stud, a scribing tool adjustably mounted on the arm, anda cutter adjustably mounted on the arm and positioned to cut the tankWall upon rotation of the arm.

5. A circle cutting tool comprising an elongated threaded stud, saidstud having a transversely disposed slot in one end, a key the length ofwhich is greater than the width frictionally retained in the slot of thestud, a washer having spaced pairs of fingers extended from one sidemounted on the stud and positioned with the fingers adapted to straddleand frictionally engage said key, said fingers being positioned toretain the key in an inclined position in the slot of the stud as thestud is passed through an opening in a Wall of a tank and to permit thekey to be moved to a transversely disposed position to preventwithdrawal of the stud from an opening in a tank Wall, an arm rotatablymounted on said stud, a scribing tool adjustably mounted on the arm, acutter adjustably mounted on the arm and positioned to cut the wall uponrotation of the arm, and resilient means for urging the arm and cuttertoward the Wall.

6. A circle cutting tool comprising an elongated threaded stud, saidstud having a transversely disposed slot in one end, a key the length ofwhich is greater than the Width frictionally retained in the slot of thestud, a Washer having spaced pairs of fingers extended from one sidemounted on the stud and positioned with the fingers adapted to straddleand frictionally engage said key, said fingers being positioned toretain the key in an inclined position in the slot of the stud as thestud is passed through an opening in a Wall of a tank and to permit thekey to be moved to a transversely disposed position to preventwithdrawal of the stud from an opening in a wall, an arm ro-tatablymounted on said stud, a scribing tool adjustably mounted on the arm, acutter adjustably mounted on the arm and positioned to cut the wall uponrotation of the arm, resilient means for urging the arm and cuttertoward the wall, and means adjusting the tension of said resilientmeans.

References Cited in the file of this patent UNITED STATES PATENTS127,934 Stone June 11, 1872 450,127 Wrigley Apr. 7, 1891 499,444Schumann June 13, 1893 1,075,759 Burridge Oct. 14, 1913 1,527,763 VanceFeb. 24, 1925 1,537,376 Prosser May 12, 1925 1,966,962 Horhorouny July17, 1934 1,971,701 Bills Aug. 28, 1934 2,230,400 Cadirola Feb. 4, 1941FOREIGN PATENTS 595,608 France July 20, 1925 795,344 France Jan. 6,

